Machines of various kinds are known for closing the upper flaps of cardboard parallelepiped boxes before applying adhesive sealing tape.
In particular so-called “self-dimensioning” machines are known, that accept boxes of various widths and heights, automatically adapting their operative parts to the dimensions of the box.
Even more in particular, “self-dimensioning” machines are known that comprise a base with support surface for resting the boxes on, a couple of drive belts that can be motorised placed at the two sides of said support surface and that can be brought close to each other to make a drive engagement with the sides of the boxes and a head above said support surface, that carries suitable devices for closing the front, rear and side flaps of the boxes and can be commanded to descend from a rest position for engaging the above-mentioned devices with the upper flaps of the boxes and thus providing for their closure. Suitable mechanical or photocell or other sensors provide for the automation of the various movements in accordance with the position and the dimensions of the boxes.
One problem encountered by the machines of this type is represented by the fact that the boxes often have the flaps partially folded outwards, therefore it is first necessary to straighten them into a vertical position and then to close them.